Mountainous Atmos.

If you’re a multi-bike rider, you’re probably familiar with how light, breathable, and comfortable road helmets can be, and have probably wished your mountain helmets could compete. Maybe you’ve even taken to wearing road helmets off-road, and deflecting the inevitable comments about spandex, shaved legs, and Lance. Well, the Giro Fathom can’t do anything about your riding partners’ senses of humor, but since it’s an Atmos with a visor, you’ll be just a bit more incognito. It gets the same, thermoformed Roll Cage SL, the Roc Loc 5 adjustment Giro helmets are famous for, and 26 vents to keep you cool, even on long, exposed, hot climbs.

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Great airflow and light

Fit is excellent no dropping down in eyes on even the roughest terrain. Best suited for XC racing.

Vernon S.

review on December 6, 2017

Light and Tight

Familiarity: I've put it through the wringer

I've been wearing Giro helmets for years and am thrilled to have upgraded to this one. The size adjuster is smoother and has more settings than prior helmets. Tons of venting and it is so light that you barely notice it's there. I just hope it offers the same protection if i bump my cabeza!

Steve Cook

review on August 6, 2017

Long time Giro user looking elsewhere

Familiarity: I returned this product before using it

I've been a HUGE proponent of giro helmets and have been wearing them exclusively for the last 10+'years. The mediums fit my head like a glove and I am currently running a synth on the road (love it) and Giro Montaro for mountain.

I ordered the fathom for a lighter XC helmet and out of the box this does NOT fit like other giro helmets as it is extremely shallow and provides very little coverage. Additionally, I was never able to get the straps to lie flat against my face, the buckle is extremely off center and and the fit is generally off. The visor is crooked (and tiny) and the helmet had a super cobby unfinished look with excess foam etc. This is the WORST effort I have ever seen from Giro. Very disappointed.

Brendan M.

review on February 25, 2017

Meets the hype!

Familiarity: I've used it several times

The Perfect helmet as described by everyone

pmikk

review on May 23, 2016

Fantastic helmet!

I love this helmet. It is so light, I barely feel it on my head. I love the look and color of it. The adjustment system is super easy to do one handed while riding.

Justin Henderson

review on April 30, 2016

Just starting to test

Familiarity: I've used it several times

Because of a very wet spring here in Utah I have not had the chance to use this much. The fit seems good so far. I will update this as I get more rides in.

Now if have several rides in the mid summer months with this helmet and it is working great. Light and airy. I am stoked.

Steven Rozendaal

review on October 8, 2015

Light & Cool

Familiarity: I've used it several times

Fit: True to size

Live in hot and humid Houston. I replaced an older Giro road helmet with a real visor that blocked the morning sun, that helmet also routed the sweat in the front around your face and no sweat drip on glasses and face until the pads wore out.

The new helmet is smaller looking lighter and well ventilated, fits well and adjustable. It is cooler than the old one.

Only negatives are the visor is useless for blocking morning sun. I removed it and went back to using a chopped cycling cap for morning sun and there are vents in front that do help cool better but you do get sweat drip.

Alan E.Height:6'6"Weight:228lbs

review on September 16, 2015

Perfect mtn bike helmet

Great fit, the straps are smaller which feels better. Awesome venting. This should last me a long time. Good value.

ROBERT BETHKE

review on September 16, 2015

Great XC Helmet

Familiarity: I've put it through the wringer

Love this helmet for XC riding. It is so light, comfy, and airy that it feels like I'm not wearing anything.

The Roc Loc 5 is awesome and easily adapts to headshape, hairstyle, and head coverings. You could for sure wear a bandana or skullcap under this helmet and still be comfortable. But then again I don't know why you would, it's just so well ventilated! I've definitely taken a few hard spills and it's showing no signs of damage.

If you're looking for a go-to lightweight XC style helmet, this is it! You won't be disappointed.

I'm a Large in most head apparel (I guess I'm filled with hot air) and this helmet was no different.

Ben brabinowitz@backcountry.com 801-746-7564

Ben Rabinowitz

Unanswered Questionquestion on June 29, 2015

How much does this helmet weigh?

Robbie Williams

review on April 29, 2015

Awesome and well vented XC helmet

Familiarity: I've used it once or twice and have initial impressions

Rode with the helmet during an Israeli spring heatwave (+30 c). Awesome ventilation, immediately you feel the air flowing all over your head. Trumps previous specialized S-works helmets with good ventilation themselves. The giro isnt as lite as the S-works but also not as expensive. If your helmet needs to be safe and vented, this is definitely the helmet for you! Giro could learn from specialized when it comes to strap endings and length that are very long and dont really solve dangly straps. I personally dont find this a big deal as the rest of the design is very aesthetic.

yaacov rabinowitz

review on March 24, 2015

Great warm weather MTB Helmet

Familiarity: I've used it several times

Living in FL, I prefer a helmet that has a lot of venting, is lightweight, and is comfortable. The Fathom does all three while still providing better protection than using a straight-up uber-light road helmet. The new wider straps and roc-loc retention make this thing very comfortable too.

A couple other little features I like are the removable visor and the small rubber plugs you put in the visor holes on the helmet to give it more of a finished look with the visor off. Also dig the extra set of pads.